PESTICIDES IN PROCESSED FOOD - MULTIRESIDUE PESTICIDES IN NATURAL GRAPE JUICES BY HIGHRESOLUTION MASS SPECTROMETRY

Grapes are among the most widely cultivated fruits in the world, with the majority of Brazilian production focusing on natural grape juice. In this work, a total of 40 samples of 2 types of natural grape juice were analyzed for the presence of 86 pesticide residues, with multiresidue extraction based on modified QuEChERS, by liquid chromatography with high-resolution mass spectrometry (LC-HRMS). Limits of detection and quantification were below 6 μg L-1 and 20 μg L-1, RSD < 20%, R2 > 0.99 and recovery ranged from 80 and 120%. Thus, the developed method was validated and good performance characteristics such as linearity, trueness, repeatability and inter-day precision were obtained. As results, 7 pesticides were detected in real samples (azoxystrobin, benalaxyl, carbendazim, tebuconazol, thiophanate-methyl, pyriproxiphen and pyrimethanil). The method was successfully validated for simultaneous evaluation of 86 multiclass pesticides residues levels, which was applied in 40 natural white and red grape juice market samples. The limits of quantification (LOQs) were low enough and the method was tested on samples showing its applicability, and therefore, this method can be used in routine analysis. Also, this work therefore also serves as an alert regarding the contamination of processed products.